It has been suggested in the literature, but never conclusively documented that frozen-deglycerolized red cells (FDRC) could prevent post-transfusion hepatitis (PTH). In a recent experiment, we showed in a chimpanzee model that FRBC did not prevent the development of type B PTH. Since 80-90% of PTH is now due to the non-A/non-B agent or agents it seems appropriate to determine if FRBC play any role in the prevention of this disease. Such a study has now become feasible because of the recent transmissions of non-A/non-B hepatitis to chimpanzees. In this study, we will utilize a human plasma pool shown to be infectious in chimpanzees, admix with RBC shown to be noninfectious and then subject this reconstituted unit of whole blood to freezing and deglycerolization. The final product will be tested for infectivity in additional chimpanzees.